Adsorption of Bezathren dyes onto sodic bentonite from aqueous solutions

The aim of the present work was to investigate the adsorption of synthetic textile dyes, such as Bezathren-Blue, Bezathren-Green and Bezathren-Red onto sodium bentonite (Bt-Na+). Adsorption experiments were performed under batch process, to assess the performance of Bt-Na+ for the removal of Bezathren-dyes, using initial dyes concentrations, pH of solution, contact time and temperature as variables. According to results, the uptake of Bezathren-dyes by Bt-Na+ was rapid and the maximum sorption was observed at lowest pH. The maximum uptake capacities (q(m)) for Bezathren-Blue, Bezathren-Green and Bezathren-Red were 35.08 mg/g, 32.88 and 48.52 mg/g respectively. Different types of adsorption isotherms and kinetic models were used to describe the Bezathren-dyes adsorption behavior. The experimental results fitted Freundlich model and the pseudo-second order kinetic models well. The results suggested that Bt-Na+ is suitable as a sorbent material for recovery and adsorption of Bezathren dyes from aqueous solutions. (C) 2017 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.